Abstract: A ?SMET platform system for ferrying supplies to soldiers in combat, evacuating the wounded, and helping transport loads. The ?SMET platform system can adjust its geometry to suit specific payloads and adapt to the terrain, is light enough to be carried by a soldier and sturdy enough to evacuate a soldier, and has adequate off-road mobility to follow an infantry unit. The ?SMET platform system's variable geometry enhances mobility over challenging terrain: its rear wheel assembly can expand to increase its stability or contract to reduce its profile.